Electrical stimulation of damaged neural tissue as a therapeutic agent has been demonstrated to be effective to restore or improve neural function in some cases. The electrical stimulation of a patient's neural tissue is accomplished by placing electrodes in contact with or in proximity to the neural tissue and applying an electrical potential to the electrodes. This necessitates the intrusion into the patient of, at a minimum, electrodes for the stimulation. Different parameters of neural stimulation may be appropriate for different patients for different types of neural injuries, and for different stages of treatment. Additionally, the appropriate length of time over which the stimuli is to be applied may vary greatly.
To minimize the potential for infection and to allow freedom from external equipment during stimulation, an implantable stimulation device is desirable. The device should have a non-invasive battery replenishment means, should be able to alter the stimulation characteristics while implanted, and should be able to transmit pertinent data out of the body with minimal energy consumption.